src/lib/reel_writer.cc

   1 /*
   2     Copyright (C) 2012-2018 Carl Hetherington <cth@carlh.net>
   3
   4     This file is part of DCP-o-matic.
   5
   6     DCP-o-matic is free software; you can redistribute it and/or modify
   7     it under the terms of the GNU General Public License as published by
   8     the Free Software Foundation; either version 2 of the License, or
   9     (at your option) any later version.
  10
  11     DCP-o-matic is distributed in the hope that it will be useful,
  12     but WITHOUT ANY WARRANTY; without even the implied warranty of
  13     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14     GNU General Public License for more details.
  15
  16     You should have received a copy of the GNU General Public License
  17     along with DCP-o-matic.  If not, see <http://www.gnu.org/licenses/>.
  18
  19 */
  20
  21 #include "reel_writer.h"
  22 #include "film.h"
  23 #include "cross.h"
  24 #include "job.h"
  25 #include "log.h"
  26 #include "digester.h"
  27 #include "font.h"
  28 #include "compose.hpp"
  29 #include "audio_buffers.h"
  30 #include "image.h"
  31 #include <dcp/mono_picture_asset.h>
  32 #include <dcp/stereo_picture_asset.h>
  33 #include <dcp/sound_asset.h>
  34 #include <dcp/sound_asset_writer.h>
  35 #include <dcp/reel.h>
  36 #include <dcp/reel_mono_picture_asset.h>
  37 #include <dcp/reel_stereo_picture_asset.h>
  38 #include <dcp/reel_sound_asset.h>
  39 #include <dcp/reel_subtitle_asset.h>
  40 #include <dcp/reel_closed_caption_asset.h>
  41 #include <dcp/dcp.h>
  42 #include <dcp/cpl.h>
  43 #include <dcp/certificate_chain.h>
  44 #include <dcp/interop_subtitle_asset.h>
  45 #include <dcp/smpte_subtitle_asset.h>
  46 #include <dcp/raw_convert.h>
  47 #include <dcp/subtitle_image.h>
  48 #include <boost/foreach.hpp>
  49
  50 #include "i18n.h"
  51
  52 #define LOG_GENERAL(...) _film->log()->log (String::compose (__VA_ARGS__), LogEntry::TYPE_GENERAL);
  53 #define LOG_GENERAL_NC(...) _film->log()->log (__VA_ARGS__, LogEntry::TYPE_GENERAL);
  54 #define LOG_WARNING_NC(...) _film->log()->log (__VA_ARGS__, LogEntry::TYPE_WARNING);
  55 #define LOG_ERROR(...) _film->log()->log (String::compose (__VA_ARGS__), LogEntry::TYPE_ERROR);
  56
  57 using std::list;
  58 using std::string;
  59 using std::cout;
  60 using boost::shared_ptr;
  61 using boost::optional;
  62 using boost::dynamic_pointer_cast;
  63 using dcp::Data;
  64 using dcp::raw_convert;
  65
  66 int const ReelWriter::_info_size = 48;
  67
  68 ReelWriter::ReelWriter (
  69         shared_ptr<const Film> film, DCPTimePeriod period, shared_ptr<Job> job, int reel_index, int reel_count, optional<string> content_summary
  70         )
  71         : _film (film)
  72         , _period (period)
  73         , _last_written_video_frame (-1)
  74         , _last_written_eyes (EYES_RIGHT)
  75         , _reel_index (reel_index)
  76         , _reel_count (reel_count)
  77         , _content_summary (content_summary)
  78 {
  79         /* Create our picture asset in a subdirectory, named according to those
  80            film's parameters which affect the video output.  We will hard-link
  81            it into the DCP later.
  82         */
  83
  84         dcp::Standard const standard = _film->interop() ? dcp::INTEROP : dcp::SMPTE;
  85
  86         if (_film->three_d ()) {
  87                 _picture_asset.reset (new dcp::StereoPictureAsset (dcp::Fraction (_film->video_frame_rate(), 1), standard));
  88         } else {
  89                 _picture_asset.reset (new dcp::MonoPictureAsset (dcp::Fraction (_film->video_frame_rate(), 1), standard));
  90         }
  91
  92         _picture_asset->set_size (_film->frame_size ());
  93
  94         if (_film->encrypted ()) {
  95                 _picture_asset->set_key (_film->key ());
  96                 _picture_asset->set_context_id (_film->context_id ());
  97         }
  98
  99         _picture_asset->set_file (
 100                 _film->internal_video_asset_dir() / _film->internal_video_asset_filename(_period)
 101                 );
 102
 103         job->sub (_("Checking existing image data"));
 104         _first_nonexistant_frame = check_existing_picture_asset ();
 105
 106         _picture_asset_writer = _picture_asset->start_write (
 107                 _film->internal_video_asset_dir() / _film->internal_video_asset_filename(_period),
 108                 _first_nonexistant_frame > 0
 109                 );
 110
 111         if (_film->audio_channels ()) {
 112                 _sound_asset.reset (
 113                         new dcp::SoundAsset (dcp::Fraction (_film->video_frame_rate(), 1), _film->audio_frame_rate (), _film->audio_channels (), standard)
 114                         );
 115
 116                 if (_film->encrypted ()) {
 117                         _sound_asset->set_key (_film->key ());
 118                 }
 119
 120                 DCPOMATIC_ASSERT (_film->directory());
 121
 122                 /* Write the sound asset into the film directory so that we leave the creation
 123                    of the DCP directory until the last minute.
 124                 */
 125                 _sound_asset_writer = _sound_asset->start_write (
 126                         _film->directory().get() / audio_asset_filename (_sound_asset, _reel_index, _reel_count, _content_summary)
 127                         );
 128         }
 129 }
 130
 131 /** @param frame reel-relative frame */
 132 void
 133 ReelWriter::write_frame_info (Frame frame, Eyes eyes, dcp::FrameInfo info) const
 134 {
 135         FILE* file = 0;
 136         boost::filesystem::path info_file = _film->info_file (_period);
 137
 138         bool const read = boost::filesystem::exists (info_file);
 139
 140         if (read) {
 141                 file = fopen_boost (info_file, "r+b");
 142         } else {
 143                 file = fopen_boost (info_file, "wb");
 144         }
 145         if (!file) {
 146                 throw OpenFileError (info_file, errno, read);
 147         }
 148         dcpomatic_fseek (file, frame_info_position (frame, eyes), SEEK_SET);
 149         fwrite (&info.offset, sizeof (info.offset), 1, file);
 150         fwrite (&info.size, sizeof (info.size), 1, file);
 151         fwrite (info.hash.c_str(), 1, info.hash.size(), file);
 152         fclose (file);
 153 }
 154
 155 dcp::FrameInfo
 156 ReelWriter::read_frame_info (FILE* file, Frame frame, Eyes eyes) const
 157 {
 158         dcp::FrameInfo info;
 159         dcpomatic_fseek (file, frame_info_position (frame, eyes), SEEK_SET);
 160         fread (&info.offset, sizeof (info.offset), 1, file);
 161         fread (&info.size, sizeof (info.size), 1, file);
 162
 163         char hash_buffer[33];
 164         fread (hash_buffer, 1, 32, file);
 165         hash_buffer[32] = '\0';
 166         info.hash = hash_buffer;
 167
 168         return info;
 169 }
 170
 171 long
 172 ReelWriter::frame_info_position (Frame frame, Eyes eyes) const
 173 {
 174         switch (eyes) {
 175         case EYES_BOTH:
 176                 return frame * _info_size;
 177         case EYES_LEFT:
 178                 return frame * _info_size * 2;
 179         case EYES_RIGHT:
 180                 return frame * _info_size * 2 + _info_size;
 181         default:
 182                 DCPOMATIC_ASSERT (false);
 183         }
 184
 185         DCPOMATIC_ASSERT (false);
 186 }
 187
 188 Frame
 189 ReelWriter::check_existing_picture_asset ()
 190 {
 191         DCPOMATIC_ASSERT (_picture_asset->file());
 192         boost::filesystem::path asset = _picture_asset->file().get();
 193
 194         /* If there is an existing asset, break any hard links to it as we are about to change its contents
 195            (if only by changing the IDs); see #1126.
 196         */
 197
 198         if (boost::filesystem::exists(asset) && boost::filesystem::hard_link_count(asset) > 1) {
 199                 boost::filesystem::copy_file (asset, asset.string() + ".tmp");
 200                 boost::filesystem::remove (asset);
 201                 boost::filesystem::rename (asset.string() + ".tmp", asset);
 202         }
 203
 204         /* Try to open the existing asset */
 205         FILE* asset_file = fopen_boost (asset, "rb");
 206         if (!asset_file) {
 207                 LOG_GENERAL ("Could not open existing asset at %1 (errno=%2)", asset.string(), errno);
 208                 return 0;
 209         } else {
 210                 LOG_GENERAL ("Opened existing asset at %1", asset.string());
 211         }
 212
 213         /* Offset of the last dcp::FrameInfo in the info file */
 214         int const n = (boost::filesystem::file_size (_film->info_file(_period)) / _info_size) - 1;
 215         LOG_GENERAL ("The last FI is %1; info file is %2, info size %3", n, boost::filesystem::file_size (_film->info_file(_period)), _info_size);
 216
 217         FILE* info_file = fopen_boost (_film->info_file(_period), "rb");
 218         if (!info_file) {
 219                 LOG_GENERAL_NC ("Could not open film info file");
 220                 fclose (asset_file);
 221                 return 0;
 222         }
 223
 224         Frame first_nonexistant_frame;
 225         if (_film->three_d ()) {
 226                 /* Start looking at the last left frame */
 227                 first_nonexistant_frame = n / 2;
 228         } else {
 229                 first_nonexistant_frame = n;
 230         }
 231
 232         while (!existing_picture_frame_ok(asset_file, info_file, first_nonexistant_frame) && first_nonexistant_frame > 0) {
 233                 --first_nonexistant_frame;
 234         }
 235
 236         if (!_film->three_d() && first_nonexistant_frame > 0) {
 237                 /* If we are doing 3D we might have found a good L frame with no R, so only
 238                    do this if we're in 2D and we've just found a good B(oth) frame.
 239                 */
 240                 ++first_nonexistant_frame;
 241         }
 242
 243         LOG_GENERAL ("Proceeding with first nonexistant frame %1", first_nonexistant_frame);
 244
 245         fclose (asset_file);
 246         fclose (info_file);
 247
 248         return first_nonexistant_frame;
 249 }
 250
 251 void
 252 ReelWriter::write (optional<Data> encoded, Frame frame, Eyes eyes)
 253 {
 254         dcp::FrameInfo fin = _picture_asset_writer->write (encoded->data().get (), encoded->size());
 255         write_frame_info (frame, eyes, fin);
 256         _last_written[eyes] = encoded;
 257         _last_written_video_frame = frame;
 258         _last_written_eyes = eyes;
 259 }
 260
 261 void
 262 ReelWriter::fake_write (Frame frame, Eyes eyes, int size)
 263 {
 264         _picture_asset_writer->fake_write (size);
 265         _last_written_video_frame = frame;
 266         _last_written_eyes = eyes;
 267 }
 268
 269 void
 270 ReelWriter::repeat_write (Frame frame, Eyes eyes)
 271 {
 272         dcp::FrameInfo fin = _picture_asset_writer->write (
 273                 _last_written[eyes]->data().get(),
 274                 _last_written[eyes]->size()
 275                 );
 276         write_frame_info (frame, eyes, fin);
 277         _last_written_video_frame = frame;
 278         _last_written_eyes = eyes;
 279 }
 280
 281 void
 282 ReelWriter::finish ()
 283 {
 284         if (!_picture_asset_writer->finalize ()) {
 285                 /* Nothing was written to the picture asset */
 286                 LOG_GENERAL ("Nothing was written to reel %1 of %2", _reel_index, _reel_count);
 287                 _picture_asset.reset ();
 288         }
 289
 290         if (_sound_asset_writer && !_sound_asset_writer->finalize ()) {
 291                 /* Nothing was written to the sound asset */
 292                 _sound_asset.reset ();
 293         }
 294
 295         /* Hard-link any video asset file into the DCP */
 296         if (_picture_asset) {
 297                 DCPOMATIC_ASSERT (_picture_asset->file());
 298                 boost::filesystem::path video_from = _picture_asset->file().get();
 299                 boost::filesystem::path video_to;
 300                 video_to /= _film->dir (_film->dcp_name());
 301                 video_to /= video_asset_filename (_picture_asset, _reel_index, _reel_count, _content_summary);
 302
 303                 boost::system::error_code ec;
 304                 boost::filesystem::create_hard_link (video_from, video_to, ec);
 305                 if (ec) {
 306                         LOG_WARNING_NC ("Hard-link failed; copying instead");
 307                         boost::filesystem::copy_file (video_from, video_to, ec);
 308                         if (ec) {
 309                                 LOG_ERROR ("Failed to copy video file from %1 to %2 (%3)", video_from.string(), video_to.string(), ec.message ());
 310                                 throw FileError (ec.message(), video_from);
 311                         }
 312                 }
 313
 314                 _picture_asset->set_file (video_to);
 315         }
 316
 317         /* Move the audio asset into the DCP */
 318         if (_sound_asset) {
 319                 boost::filesystem::path audio_to;
 320                 audio_to /= _film->dir (_film->dcp_name ());
 321                 string const aaf = audio_asset_filename (_sound_asset, _reel_index, _reel_count, _content_summary);
 322                 audio_to /= aaf;
 323
 324                 boost::system::error_code ec;
 325                 boost::filesystem::rename (_film->file (aaf), audio_to, ec);
 326                 if (ec) {
 327                         throw FileError (
 328                                 String::compose (_("could not move audio asset into the DCP (%1)"), ec.value ()), aaf
 329                                 );
 330                 }
 331
 332                 _sound_asset->set_file (audio_to);
 333         }
 334 }
 335
 336 template <class T>
 337 void
 338 maybe_add_text (
 339         shared_ptr<dcp::SubtitleAsset> asset,
 340         int64_t picture_duration,
 341         shared_ptr<dcp::Reel> reel,
 342         list<ReferencedReelAsset> const & refs,
 343         list<shared_ptr<Font> > const & fonts,
 344         shared_ptr<const Film> film,
 345         DCPTimePeriod period
 346         )
 347 {
 348         Frame const period_duration = period.duration().frames_round(film->video_frame_rate());
 349
 350         shared_ptr<T> reel_asset;
 351
 352         if (asset) {
 353
 354                 boost::filesystem::path liberation_normal;
 355                 try {
 356                         liberation_normal = shared_path() / "LiberationSans-Regular.ttf";
 357                         if (!boost::filesystem::exists (liberation_normal)) {
 358                                 /* Hack for unit tests */
 359                                 liberation_normal = shared_path() / "fonts" / "LiberationSans-Regular.ttf";
 360                         }
 361                 } catch (boost::filesystem::filesystem_error& e) {
 362
 363                 }
 364
 365                 if (!boost::filesystem::exists(liberation_normal)) {
 366                         liberation_normal = "/usr/share/fonts/truetype/liberation/LiberationSans-Regular.ttf";
 367                 }
 368
 369                 /* Add all the fonts to the subtitle content */
 370                 BOOST_FOREACH (shared_ptr<Font> j, fonts) {
 371                         asset->add_font (j->id(), j->file(FontFiles::NORMAL).get_value_or(liberation_normal));
 372                 }
 373
 374                 if (dynamic_pointer_cast<dcp::InteropSubtitleAsset> (asset)) {
 375                         boost::filesystem::path directory = film->dir (film->dcp_name ()) / asset->id ();
 376                         boost::filesystem::create_directories (directory);
 377                         asset->write (directory / ("sub_" + asset->id() + ".xml"));
 378                 } else {
 379
 380                         /* All our assets should be the same length; use the picture asset length here
 381                            as a reference to set the subtitle one.  We'll use the duration rather than
 382                            the intrinsic duration; we don't care if the picture asset has been trimmed, we're
 383                            just interested in its presentation length.
 384                         */
 385                         dynamic_pointer_cast<dcp::SMPTESubtitleAsset>(asset)->set_intrinsic_duration (picture_duration);
 386
 387                         asset->write (
 388                                 film->dir(film->dcp_name()) / ("sub_" + asset->id() + ".mxf")
 389                                 );
 390                 }
 391
 392                 reel_asset.reset (
 393                         new T (
 394                                 asset,
 395                                 dcp::Fraction (film->video_frame_rate(), 1),
 396                                 picture_duration,
 397                                 0
 398                                 )
 399                         );
 400         } else {
 401                 /* We don't have a subtitle asset of our own; hopefully we have one to reference */
 402                 BOOST_FOREACH (ReferencedReelAsset j, refs) {
 403                         shared_ptr<T> k = dynamic_pointer_cast<T> (j.asset);
 404                         if (k && j.period == period) {
 405                                 reel_asset = k;
 406                                 /* If we have a hash for this asset in the CPL, assume that it is correct */
 407                                 if (k->hash()) {
 408                                         k->asset_ref()->set_hash (k->hash().get());
 409                                 }
 410                         }
 411                 }
 412         }
 413
 414         if (reel_asset) {
 415                 if (reel_asset->duration() != period_duration) {
 416                         throw ProgrammingError (
 417                                 __FILE__, __LINE__,
 418                                 String::compose ("%1 vs %2", reel_asset->duration(), period_duration)
 419                                 );
 420                 }
 421                 reel->add (reel_asset);
 422         }
 423 }
 424
 425 shared_ptr<dcp::Reel>
 426 ReelWriter::create_reel (list<ReferencedReelAsset> const & refs, list<shared_ptr<Font> > const & fonts)
 427 {
 428         shared_ptr<dcp::Reel> reel (new dcp::Reel ());
 429
 430         shared_ptr<dcp::ReelPictureAsset> reel_picture_asset;
 431
 432         if (_picture_asset) {
 433                 /* We have made a picture asset of our own.  Put it into the reel */
 434                 shared_ptr<dcp::MonoPictureAsset> mono = dynamic_pointer_cast<dcp::MonoPictureAsset> (_picture_asset);
 435                 if (mono) {
 436                         reel_picture_asset.reset (new dcp::ReelMonoPictureAsset (mono, 0));
 437                 }
 438
 439                 shared_ptr<dcp::StereoPictureAsset> stereo = dynamic_pointer_cast<dcp::StereoPictureAsset> (_picture_asset);
 440                 if (stereo) {
 441                         reel_picture_asset.reset (new dcp::ReelStereoPictureAsset (stereo, 0));
 442                 }
 443         } else {
 444                 LOG_GENERAL ("no picture asset of our own; look through %1", refs.size());
 445                 /* We don't have a picture asset of our own; hopefully we have one to reference */
 446                 BOOST_FOREACH (ReferencedReelAsset j, refs) {
 447                         shared_ptr<dcp::ReelPictureAsset> k = dynamic_pointer_cast<dcp::ReelPictureAsset> (j.asset);
 448                         if (k) {
 449                                 LOG_GENERAL ("candidate picture asset period is %1-%2", j.period.from.get(), j.period.to.get());
 450                         }
 451                         if (k && j.period == _period) {
 452                                 reel_picture_asset = k;
 453                         }
 454                 }
 455         }
 456
 457         LOG_GENERAL ("create_reel for %1-%2; %3 of %4", _period.from.get(), _period.to.get(), _reel_index, _reel_count);
 458
 459         Frame const period_duration = _period.duration().frames_round(_film->video_frame_rate());
 460
 461         DCPOMATIC_ASSERT (reel_picture_asset);
 462         if (reel_picture_asset->duration() != period_duration) {
 463                 throw ProgrammingError (
 464                         __FILE__, __LINE__,
 465                         String::compose ("%1 vs %2", reel_picture_asset->duration(), period_duration)
 466                         );
 467         }
 468         reel->add (reel_picture_asset);
 469
 470         /* If we have a hash for this asset in the CPL, assume that it is correct */
 471         if (reel_picture_asset->hash()) {
 472                 reel_picture_asset->asset_ref()->set_hash (reel_picture_asset->hash().get());
 473         }
 474
 475         shared_ptr<dcp::ReelSoundAsset> reel_sound_asset;
 476
 477         if (_sound_asset) {
 478                 /* We have made a sound asset of our own.  Put it into the reel */
 479                 reel_sound_asset.reset (new dcp::ReelSoundAsset (_sound_asset, 0));
 480         } else {
 481                 /* We don't have a sound asset of our own; hopefully we have one to reference */
 482                 BOOST_FOREACH (ReferencedReelAsset j, refs) {
 483                         shared_ptr<dcp::ReelSoundAsset> k = dynamic_pointer_cast<dcp::ReelSoundAsset> (j.asset);
 484                         if (k && j.period == _period) {
 485                                 reel_sound_asset = k;
 486                                 /* If we have a hash for this asset in the CPL, assume that it is correct */
 487                                 if (k->hash()) {
 488                                         k->asset_ref()->set_hash (k->hash().get());
 489                                 }
 490                         }
 491                 }
 492         }
 493
 494         DCPOMATIC_ASSERT (reel_sound_asset);
 495         if (reel_sound_asset->duration() != period_duration) {
 496                 LOG_ERROR (
 497                         "Reel sound asset has length %1 but reel period is %2",
 498                         reel_sound_asset->duration(),
 499                         period_duration
 500                         );
 501                 if (reel_sound_asset->duration() != period_duration) {
 502                         throw ProgrammingError (
 503                                 __FILE__, __LINE__,
 504                                 String::compose ("%1 vs %2", reel_sound_asset->duration(), period_duration)
 505                                 );
 506                 }
 507
 508         }
 509         reel->add (reel_sound_asset);
 510
 511         maybe_add_text<dcp::ReelSubtitleAsset>      (_text_asset[TEXT_OPEN_SUBTITLE],  reel_picture_asset->duration(), reel, refs, fonts, _film, _period);
 512         maybe_add_text<dcp::ReelClosedCaptionAsset> (_text_asset[TEXT_CLOSED_CAPTION], reel_picture_asset->duration(), reel, refs, fonts, _film, _period);
 513
 514         return reel;
 515 }
 516
 517 void
 518 ReelWriter::calculate_digests (boost::function<void (float)> set_progress)
 519 {
 520         if (_picture_asset) {
 521                 _picture_asset->hash (set_progress);
 522         }
 523
 524         if (_sound_asset) {
 525                 _sound_asset->hash (set_progress);
 526         }
 527 }
 528
 529 Frame
 530 ReelWriter::start () const
 531 {
 532         return _period.from.frames_floor (_film->video_frame_rate());
 533 }
 534
 535
 536 void
 537 ReelWriter::write (shared_ptr<const AudioBuffers> audio)
 538 {
 539         if (!_sound_asset_writer) {
 540                 return;
 541         }
 542
 543         DCPOMATIC_ASSERT (audio);
 544         _sound_asset_writer->write (audio->data(), audio->frames());
 545 }
 546
 547 void
 548 ReelWriter::write (PlayerText subs, TextType type, DCPTimePeriod period)
 549 {
 550         if (!_text_asset[type]) {
 551                 string lang = _film->subtitle_language ();
 552                 if (lang.empty ()) {
 553                         lang = "Unknown";
 554                 }
 555                 if (_film->interop ()) {
 556                         shared_ptr<dcp::InteropSubtitleAsset> s (new dcp::InteropSubtitleAsset ());
 557                         s->set_movie_title (_film->name ());
 558                         s->set_language (lang);
 559                         s->set_reel_number (raw_convert<string> (_reel_index + 1));
 560                         _text_asset[type] = s;
 561                 } else {
 562                         shared_ptr<dcp::SMPTESubtitleAsset> s (new dcp::SMPTESubtitleAsset ());
 563                         s->set_content_title_text (_film->name ());
 564                         s->set_language (lang);
 565                         s->set_edit_rate (dcp::Fraction (_film->video_frame_rate (), 1));
 566                         s->set_reel_number (_reel_index + 1);
 567                         s->set_time_code_rate (_film->video_frame_rate ());
 568                         s->set_start_time (dcp::Time ());
 569                         if (_film->encrypted ()) {
 570                                 s->set_key (_film->key ());
 571                         }
 572                         _text_asset[type] = s;
 573                 }
 574         }
 575
 576         BOOST_FOREACH (StringText i, subs.string) {
 577                 /* XXX: couldn't / shouldn't we use period here rather than getting time from the subtitle? */
 578                 i.set_in  (i.in()  - dcp::Time (_period.from.seconds(), i.in().tcr));
 579                 i.set_out (i.out() - dcp::Time (_period.from.seconds(), i.out().tcr));
 580                 _text_asset[type]->add (shared_ptr<dcp::Subtitle>(new dcp::SubtitleString(i)));
 581         }
 582
 583         BOOST_FOREACH (BitmapText i, subs.bitmap) {
 584                 _text_asset[type]->add (
 585                         shared_ptr<dcp::Subtitle>(
 586                                 new dcp::SubtitleImage(
 587                                         i.image->as_png(),
 588                                         dcp::Time(period.from.seconds(), _film->video_frame_rate()),
 589                                         dcp::Time(period.to.seconds(), _film->video_frame_rate()),
 590                                         i.rectangle.x, dcp::HALIGN_LEFT, i.rectangle.y, dcp::VALIGN_TOP,
 591                                         dcp::Time(), dcp::Time()
 592                                         )
 593                                 )
 594                         );
 595         }
 596 }
 597
 598 bool
 599 ReelWriter::existing_picture_frame_ok (FILE* asset_file, FILE* info_file, Frame frame) const
 600 {
 601         LOG_GENERAL ("Checking existing picture frame %1", frame);
 602
 603         /* Read the data from the info file; for 3D we just check the left
 604            frames until we find a good one.
 605         */
 606         dcp::FrameInfo const info = read_frame_info (info_file, frame, _film->three_d () ? EYES_LEFT : EYES_BOTH);
 607
 608         bool ok = true;
 609
 610         /* Read the data from the asset and hash it */
 611         dcpomatic_fseek (asset_file, info.offset, SEEK_SET);
 612         Data data (info.size);
 613         size_t const read = fread (data.data().get(), 1, data.size(), asset_file);
 614         LOG_GENERAL ("Read %1 bytes of asset data; wanted %2", read, info.size);
 615         if (read != static_cast<size_t> (data.size ())) {
 616                 LOG_GENERAL ("Existing frame %1 is incomplete", frame);
 617                 ok = false;
 618         } else {
 619                 Digester digester;
 620                 digester.add (data.data().get(), data.size());
 621                 LOG_GENERAL ("Hash %1 vs %2", digester.get(), info.hash);
 622                 if (digester.get() != info.hash) {
 623                         LOG_GENERAL ("Existing frame %1 failed hash check", frame);
 624                         ok = false;
 625                 }
 626         }
 627
 628         return ok;
 629 }